Standing at 6’2, Day has strong experience in non-league football, having also featured for Scarborough Athletic, Guiseley, Alfreton Town and Bridlington Town throughout his career.
Last season, the 30-year-old helped Scarborough secure promotion to the National League North via the Pitching In NPL Premier Division play-offs.
"I just wanted to get playing again and the gaffer's given me that opportunity. I'm looking forward to getting going,” he said.
"It's not been the best start for the club so hopefully I can come in and make a difference, score some goals and start getting some points on the board.
"Nathan's just said to me that there's a great setup and some great players, but they just haven't had the run of the green so hopefully if the lads get the ball into the box, I can get the goals."
Whitby Town manager Nathan Haslam said: "I'm really, really happy to have Jake here. It's taken a lot of hard work and a lot of conversations.
"It soon became evident that we were lacking a target man and someone to put their neck on the line for us.
"We've got some exceptional footballers but we haven't got this type of player.
“Jake's arrival will give us a new dimension in the way that we play and it certainly looks like he's the missing piece in the jigsaw."
Photo credit: Whitby Town
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